Springless dial-scale.



UNITED STATES PATENT OFFICE.

Specification of Letters Patent.

Patented Nov. 13, 1906.

Application filed January 29, 1906. filerial No: 298312.

To all whom it may concern;

Be it known that I, FRANK H. BROWN, a citizen of the United States, and a resident of St. Louis, Missouri, have invented certain new and useful Im rovements in Springless Dial-Scales, of Whic the following is a specification containing a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

My invention relates to a springless dialscale; and the object of my invention is to provide a dial-scale with mechanism which will instantly return the indicating-finger back to zero after the weighing operation is complete and the load has been removed from the scale-platform.

Heretofore dial-scales have been provided with spring-actuated mechanism for returning the indicating-finger; but springs are more or less unreliable, easily get out of order, and in time become weakened, and I proose to rovide a mechanism with a weight which Wlll be elevated when a load is weighed and which will descend when the load is removed from the scale-platform and return the indicating-finger to the zero-mark upon the dial.

. To the above pur oses my invention consists of certain nove features of construction and arrangement of arts, which will be hereinafter more cleary set forth, pointed out in my claim, and illustrated in the accompanying drawings, in which Figure 1 is a perspective view of a scale constructed in accordance with my invention. Fig. 2 is an enlarged vertical section taken on the line 2 2 of Fig. 1. Fig. 3 is a vertical section taken on the line 3 3 of Fig. 2.

Referring by numerals to the accompanyinghdrawings, 1 indicates the scale-platform, 2 t e vertically-arranged housing at the rear of the platform, and 8 the dial upon the front side of the upper end of said housing.

J ournaled in the center of the dial 3 and in a bearing 4, that is fixed to the inner face of the rear wall of the housing 3, is a horizontally-arranged shaft 5, on the forward end of which is fixed the indicating-finger 6. Mounted on the shaft 5 adjacent the bearing 4 is a pinion 7. Arranged for rotation upon a stub-shaft 8, that extends inwardly from the inside face of the rear wall of the housing2, is a inion 9, which meshes with the pimon 7. ournaled in bearin s 10, that are fixed to the inside face of one of the side walls of the housing 2, is a shaft 11, upon which is mounted a large ear-wheel 12, with which the pinion 9 mes es. short distance from the gear-wheel 12 is a pinion 13, and fixed to and depending from the shaft 11, adjacent said pinion, is an arm weight 15. Arranged to slide vertlcally through a guide 16, that is-fixed to the rear wall of the housing 2, is a rack-bar 17, the teeth of which mesh with the pinion 13. Pivotally connected to the lower end of this rack-bar is a horizontally-arranged lever 18, which is fulcrumed at its opposite end to a bearing 19, fixed to one of the side walls of the .housing 2. Pivotally connected to the lever 18 adjacent its center is the u per end of a verticall arranged rod 20, whic is connected at its lower end to the Wei hing mechanism arranged in the base of t e scale beneath the platform 1.

The variousparts of the mechanism just described are so arranged as that when the weight '15 is at its lowermost position and the arm 14 is vertical the indicatin -finger 6 is at the zero-point on the scale of t e dial 3. When a load is placed upon the scale-platform 1, the rod 20 is moved downwardly, and as a result the end of the lever 18 to which the lower end of the rack-bar 17 is pivoted is likewise moved downwardly. This movement necessarily rotates the shaft 11 as the teeth of the rack-bar 17 mesh with the pinion 13, and consequently the gearwheel 12 is rotated in the direction indicated by the arrow in Fig. 2. This rotary motion is transmitted, by means of the pinion 9, to the pinion 7 and shaft 5, and as a result the indicating-finger 6 moves around upon the scale of the dial to indicate the weight of the load upon the scale-platform.

As soon as the load is removed from the platform the weighing mechanism beneath said platform will reassume its normal position and the rod 20 will move upwardly a slight distance. Following this action the weight 15 will swing downwardly to its normal position, bringing the rod 14 into vertical position, and the rack-bar 17, together with the various pinions and gear-wheel, will move in reverse directions to the movements finger 6 will return to the zerooint upon the dial. Dotted lines in Fig. 2 il ustrate the swing of the arm 14 and weight 15.

The mechanism herein described operates i freely and accurately, and the weight in 14, on the lower end of which is arranged ajust described, and as a result the indicating- Fixed upon this shaft 11 a I swinging to its normal position after having been elevated quickly and positively returns the indicating-finger to the zero point, and as the various operating parts are cared together there wil be no vlbration o the indicating-finger. after its return to the zeropoint, as is the case where springs are made use of. The device is simple, inexpensive, is positive in operation, and can be readily applied to all forms of platform-scales.

I claim In a dial-scale, the combination with the indicating-finger of adial and Weighing mechanism, of a train of gearing leading from the shaft on which the Indicating-finger is positioned, a shaft mounted for rotation adjacent said train of gearing, a large gearwheel mounted on said shaft and meshing with one of the pinions of the train of gearing,- a pinion mounted upon the shaft, a vertically-disposed rack enga ing the pinion, a bearing through which t e u per-end of said rack operates, a horizonta ly-disposed lever fulcrumed at one end and pivotally connected at its outer end to the lower end of the rack and to which lever is connected one of the levers of the weighing mechanismyan arm fixed to and depending from the shaft, and a weight carried by the lower .end of said arm; substantially as specified.

In testimony whereof I have signed my name to this specification in presence of two subscribing witnesses.

FRANK H. BROWN. 

